JP3305130B2 - Ink jet head and ink jet device provided with the ink jet head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head and an ink jet apparatus provided with the ink jet head. More specifically, the present invention relates to an ink jet head in which a sealing material made of a specific silicone-modified epoxy resin is disposed at a joint of members constituting an ink supply path, and an ink jet device including the ink jet head.

[0002]

2. Description of the Related Art In an ink jet head, there is a case where ink discharged to a print medium leaks from a joint portion of members constituting an ink supply path from an ink tank to a discharge port. In some cases, the medium is contaminated. Also, if bubbles exist in the ink flow path of the ink jet head, the ejection energy is attenuated by the bubbles, and normal ejection may not be performed. For this reason, in the ink-jet head, a sealing material is provided at a joining portion of the ink-jet head and a constituent member constituting the ink supply path for the purpose of preventing ink leakage and mixing of bubbles into the ink supply path. I have.

FIGS. 1 to 4 show examples of a conventional ink jet head provided with such a sealing material and an apparatus equipped with the ink jet head.

FIG. 1 is a schematic perspective view showing an example of a conventional ink jet head. FIG. 2 is a cross-sectional view of a main part of the ink-jet head when an AB cut surface obtained by cutting the ink-jet head of FIG. 1 along an ink flow path is viewed from an arrow direction. FIG. 3 is a schematic perspective view of a discharge element portion of the ink jet head shown in FIG. FIG. 4 shows FIG.
FIG. 3 is a schematic explanatory view showing an example of an ink jet device equipped with the ink jet head shown in FIG.

In FIG. 1, reference numeral 1 denotes an ink jet head, to which an ink supply unit 2 for supplying ink is connected. The ink supply unit 2 is connected to an ink tank 5 via a supply tube 3. This ink tank 5 is an aluminum base plate 4 supporting an inkjet head.
And an ink tank 5B for storing black ink and an ink tank 5C for storing yellow, magenta, and cyan ink, with a supply tube inserted into each of the ink tanks so that the supply tube 3 is joined thereto. A unit 6 is provided, and is detachably connected to the ink supply unit 2.

As shown in FIGS. 2 and 3, the ink-jet head 1 has a heating element 103, which is an electrothermal converter, and a heating element wiring 102 formed on a silicon substrate 101 by using a thin film forming technique. On the silicon substrate on which the electrothermal transducer is formed, there are further provided an ink flow path wall 104a and a common ink chamber wall 104b formed of a resin such as a photosensitive resin. And
A top plate 105 made of a glass substrate is adhered so as to cover the concave portion formed by the ink passage wall 104 to form an ink passage and a common ink chamber. The top plate 105
Is provided with an opening serving as a common ink inlet 107. The common ink inlet 107 is covered with an ink filter 106 adhered to a top plate 105.
A sealing material 110 is applied to the top plate 105 by a dispenser, screen printing, or the like, and an ink supply unit 2 is connected to the common ink inlet via the sealing material 110.

FIG. 4 is a schematic explanatory view showing an example of an ink jet apparatus (IJA) in which the ink jet head of FIG. 1 is mounted as an ink jet head cartridge (IJC).

In FIG. 4, reference numeral 20 denotes an ink jet head cartridge (IJC) provided with a nozzle group for discharging ink while facing a print surface of a print medium as a print medium sent on a platen 24. 1
Reference numeral 6 denotes a carriage HC for holding the IJC 20, which is connected to a part of the drive belt 18 for transmitting the driving force of the drive motor 17, and is slidable with two guide shafts 19A and 19B disposed in parallel with each other. By doing, IJ
Reciprocal movement over the entire width of the C20 print paper is enabled.

Reference numeral 26 denotes a head recovery device, which is an IJC20.
, For example, at a position facing the home position. The IJC 20 is capped by the driving force of the motor 22 via the transmission mechanism 23.
Also, by performing capping with the cap member 26A at the end of printing or the like, the IJC is protected.

Reference numeral 30 denotes a blade disposed on a side surface of the head recovery device 26 and formed as a wiping member made of silicone rubber. The blade 30 is a blade holding member 30
A is held in a cantilever form, and the head recovery device 26
Similarly to the above, it is operated by the motor 22 and the transmission mechanism 23, and can be engaged with the discharge surface of the IJC 20. Thus, at an appropriate timing in the recording operation of the IJC 20, or after the ejection recovery processing using the head recovery device 26, the blade 30 is projected into the movement path of the IJC 20, and the ejection surface of the IJC 20 is moved with the movement operation of the IJC 20. To remove condensation, wetness, dust and the like.

As described above, since the sealing material provided in the ink jet head is provided in a portion in contact with the ink, if the sealing material, which is a starting material for forming the sealing material, is excessively applied, the formed sealing material will not be formed. Part of the material may enter the ink flow path. In the worst case, when the sealing material enters the ink flow path, the nozzle may be clogged. Therefore, the sealing material is formed using a sealing material that is liquid at normal temperature so that the amount of coating can be strictly controlled so that the sealing material does not enter the ink flow path. As a material for forming the sealing material, a solventless material which is liquid at room temperature is used. The reason why the sealing material is formed using such a solventless material is as follows.
That is, since the sealing material is provided at a position in contact with the ink, if a solvent is contained in the sealing material, the solvent may elute into the ink and change the composition of the ink. In some cases, this may lead to ink ejection failure. Since the sealing material is provided at the joint of the constituent members of the ink supply path, care must be taken in its formation so as not to affect the accuracy of assembling the inkjet head. For this reason, it is preferable that the sealing material is formed using a one-pack type material that has a long pot life and does not need to consider the pot life substantially.

[0012] In addition, as a function requirement of the ink jet head, low stress property and high ink resistance are required in addition to the above-described airtightness and liquid tightness.

That is, as described above, when a material having a high coefficient of thermal expansion is used as a component of the head, such as the ink passage wall, a large stress due to thermal expansion is applied to the sealing material provided around the ejection element. For this reason, the sealing material may peel off due to this stress. Therefore,
The problem of peeling is solved by giving the sealing material an elastic force (low stress property) to absorb this stress. This elastic force works effectively even when the ink jet head receives an impact in a recovery process such as wiping.

Further, since the sealing material is provided at a position which is in direct contact with the ink, the sealing material has high ink resistance, that is, the performance of the sealing material is not deteriorated by the ink, and It is required that the material does not generate effluent that adversely affects the performance of the ink.

As described above, the sealing material provided in the ink jet head is required to satisfy the above-described requirements for the sealing material comprehensively and sufficiently exhibit the sealing function.

In view of the above, a silicone rubber sealant has conventionally been used as a sealing material provided in an ink jet head.

When air bubbles enter the common ink chamber and the ink flow path in the ink jet head for some reason, a timer and a manual provided in the printer body are usually provided to remove the air bubbles. The recovery process of the inkjet head is performed by using recovery means such as a suction pump operated by the operation. At this time, especially when air bubbles are retained upstream of the energy generator in the ink supply direction, it is necessary to perform the recovery process with a considerable suction force. On the other hand, in recent years, as the size of the apparatus has been required to be reduced, the capacity of the ink tank tends to decrease. This tendency is particularly remarkable in a cartridge type ink jet apparatus in which an ink tank is mounted on a carriage. When the capacity of the ink tank is small as described above, it is desirable to use as little ink as possible for purposes other than those used for printing. Therefore, it is preferable that the above-described recovery processing is not performed as much as possible. It is considered that the above-mentioned bubbles are mixed in the ink-jet head when the ink is mixed during the manufacturing process of the ink-jet head and when the gas dissolved in the ink is released due to a rise in the temperature at the time of ejection. But,
If these are once subjected to a recovery process before the product is shipped, no bubbles are mixed during use.

However, when the ink-jet head after the recovery processing is kept unused for a long time, air bubbles may be generated in the ink-jet head. This is mainly due to the intrusion of air from the sealing portion that seals the joining portion of the members constituting the ink supply path.

That is, since the silicone rubber sealant conventionally used as a sealing material in the sealing portion has a high gas permeability, there is no problem in normal use, but when the ink is not used for a long period of time, the ink is discharged from the opening. Evaporates little by little, and air enters instead from the common ink inlet and the ink supply unit seam where airtightness is maintained by the silicone rubber sealant to compensate for the pressure difference due to the evaporation of the ink. Bubbles are generated. In this case, the above-described recovery processing is required. Therefore, it is conceivable to use an epoxy resin, which is a material having excellent gas barrier properties, as a sealing material used for an ink jet head. However, since the epoxy resin has low flexibility in terms of the stress described above, the May cause peeling,
It was not preferable as a sealing material used for an ink jet head. It is also conceivable to use an elastic epoxy resin having improved flexibility of the epoxy resin as a sealing material for the inkjet head. However, although the gas barrier property and the flexibility are satisfactory, the ink resistance is not sufficient because the ink resistance is not sufficient. It was not preferable as a sealing material used for the above.

On the other hand, in recent years, ink jet apparatuses have been used in fields other than printers such as copying machines and textile printing apparatuses, and ink may be attached to print media other than paper, such as OHP sheets and cloths. . Further, the printed matter may be made more water-resistant. In such a case, inks having high alkalinity have been used for the purpose of improving fixability and water resistance. That is, in order to improve fixability and water resistance, a dye that is relatively insoluble in a solvent or a pigment that is difficult to disperse may be used as a dye or pigment of the ink, and exhibits high alkalinity in order to make full use of these dyes and pigments. By using ink, the dyes become easier to dissolve,
In addition, pigments have improved dispersion stability. As inks exhibiting such high alkalinity are used, improvement in ink resistance of the sealing material is required. In the case where the ink jet head using the high alkali ink actually remains unused for a long time, the amount of bubbles mixed into the ink flow path is larger than before, and the ink jet head using the high alkali ink is used. When the sealing material was observed, peeling of the sealing material was also observed. Further, when the sealing material is provided near the wiring depending on the form of the inkjet head, a short circuit between the electrodes may be observed.

[0021]

SUMMARY OF THE INVENTION It is a primary object of the present invention to provide an ink jet head improved by solving the above-mentioned problems in the prior art and an ink jet apparatus provided with the ink jet head.

Another object of the present invention is to provide an ink supply passage having a joint portion which is excellent in liquid and gas barrier properties and does not peel off even in an environment having a temperature change. Another object of the present invention is to provide an inkjet head using a sealing material having high ink resistance and an inkjet apparatus including the inkjet head.

Another object of the present invention is to provide an ink jet head which does not require a recovery process due to the generation of air bubbles and has an excellent amount of ink used even in a small ink tank, and an ink jet apparatus having the ink jet head. .

Another object of the present invention is to provide an ink jet head having a sealing material which does not cause generation of air bubbles or peeling of the sealing material even when a highly alkaline ink is used, and an ink jet apparatus having the ink jet head. To provide.

Another object of the present invention is to provide an ink jet head capable of maintaining excellent print quality even when the ink jet head has not been used for a long time, and an ink jet apparatus provided with the ink jet head.

[0026]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the prior art, and has been completed as a result of intensive studies through experiments by the present inventors in order to achieve the above objects. .

That is, the present inventors have paid attention to the excellent gas barrier property of the epoxy resin, improved the stress problem of the epoxy resin while exhibiting the gas barrier property, and further improved the ink resistance as compared with the related art. When examining the feasibility of a sealing material with excellent performance, the sealing material consisting of a silicone-modified epoxy resin and a latent curing agent was excellent in airtightness, low stress, and high ink resistance. When the material is used for the joint portion of the members constituting the ink supply path of the ink jet head, even when the above-described recovery processing is not performed in a long-term use, or when the high alkali ink is used, the unused state is not used for a long time. It has been found that even in the following case, the ink can be stably ejected without peeling of the sealing material.

The object of the present invention is to provide a liquid at room temperature.
Sealing a solvent-free, one-pack type silicone-modified epoxy resin-based composition substantially consisting of a latent curing agent (hereinafter sometimes referred to as a silicone-modified epoxy resin composition). It is achieved by using it as a material.

That is, the ink jet head of the present invention
It is characterized by having a sealing material formed using the silicone-modified epoxy resin composition described above.

In the present invention, the silicone-modified epoxy resin contains 10 to 60 parts by weight of a silicone component based on 100 parts by weight of the raw material epoxy resin (that is, 10 to 60 parts by weight of silicone based on 100 parts by weight of the starting epoxy resin). Component is added).

The ink-jet head of the present invention includes a mode in which electric energy is given by an electrothermal converter to generate heat to cause a change in the state of the ink to discharge the ink.

Further, the ink jet head of the present invention comprises:
It includes a full-line type in which a plurality of ejection ports are provided over the entire width of the print area of the print medium.

Further, the present invention includes an ink jet device having a sealing material formed using the above silicone-modified epoxy resin composition.

In the present invention, the term "sealing material" is used for the purpose of protecting the sealing portion of the ink jet head from an external environment such as moisture, vibration and shock, and at the same time, improving electrical insulation and heat dissipation. Member ". As mentioned above,
The sealing material according to the present invention is formed of the above-described silicone-modified epoxy resin composition (that is, substantially composed of the above-described silicone-modified epoxy resin and a latent curing agent). The silicone-modified epoxy resin composition may contain components such as a filler such as silica and carbon black, a thixotropic agent such as Aerosil, and a pigment, if necessary.

The above-mentioned silicone-modified epoxy resin, which is a main component of the sealing material of the present invention, is prepared using epoxy resin and organosiloxane as raw materials.

The encapsulant of the present invention is usually formed by applying the above-mentioned silicone-modified epoxy resin composition to an ink jet head by a dispenser or screen printing. It needs to be liquid. In particular, in the case of an ink jet head, it is necessary to pour the silicone-modified epoxy resin composition into a very narrow part, so that the silicone-modified epoxy resin composition needs to have a low viscosity. The specific viscosity is 10 to 100000p
s.

It is desirable that the silicone-modified epoxy resin composition is a solvent-free one in addition to being liquid at room temperature. The reason for this is that since the sealing material is usually formed in a sealed portion, when the silicone-modified epoxy resin composition is a solvent system, the solvent gasifies at the time of curing and causes voids in the sealing material. There is a problem that the solvent sealed without drying is eluted from the portion in contact with the ink, thereby changing the physical properties of the ink.

The epoxy resin used as a raw material of the silicone-modified epoxy resin used in the present invention may be any resin as long as it has two or more epoxy groups in one molecule and is liquid at normal temperature. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol AF type epoxy resin, novolak type epoxy resin, and modified resins thereof can be used. These epoxy resins are 1
Species or a mixture of two or more can be used. It is desirable that these epoxy resins have ionic impurities such as Na ⁺ and Cl ⁻ removed as much as possible.

As the above-mentioned organosiloxane used in the present invention, those having a functional group capable of reacting with the above-mentioned epoxy resin are used. As the functional group,
Examples include an epoxy group, an alkoxy group, a hydroxyl group, an amino group, and a hydrosilyl group. The molecular structure of the organosiloxane may be linear or branched. The organopolysiloxane used in the present invention is:
Specifically, organosiloxanes represented by the following formulas (I), (II) and (III) can be used. These are examples and the present invention is not limited to these.

[0040]

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[0041]

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[0042]

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The silicone-modified epoxy resin used in the present invention can be produced by a known constitution method.
Specific examples of such a synthesis method include (1) a synthesis method of reacting an organopolysiloxane having an amino group with a part of epoxy groups of an epoxy resin to obtain an adduct, and (2) an alkenyl group-containing epoxy resin and a hydrogel. A synthesis method of obtaining an adduct of a silyl group-containing organopolysiloxane by a hydrosilylation reaction in the presence of a chloroplatinic acid catalyst can be mentioned.

Among these synthesis methods, the method of obtaining the silicone-modified epoxy resin of the present invention by the synthesis method (2) is carried out, for example, as follows.

A mixture of 2-allylphenol and tributylamine was added dropwise to a predetermined amount of bisphenol A type epoxy resin while stirring at a temperature of 110 ° C., and then stirred at a temperature of 110 ° C. for a predetermined time. I do.
Unreacted 2-allylphenol and tributylamine are distilled off from the obtained product under reduced pressure to obtain an alkenyl group-containing epoxy resin. Next, a predetermined amount of the obtained alkenyl group-containing epoxy resin is mixed with a solvent (for example, a mixed solvent of methyl isobutyl ketone and toluene) with a predetermined amount of the epoxy resin.
Mix with 2-ethylhexanol-modified chloroplatinic acid solution,
Perform azeotropic dehydration. At the reflux temperature, an organopolysiloxane is added dropwise to the obtained mixture, and the mixture is stirred at a temperature of 110 ° C. to carry out a reaction. The obtained product is washed with water, and the solvent is distilled off under reduced pressure. This gives a crude reaction product. Dissolve the obtained crude reaction product in acetone,
Water is added to the mixture and the mixture is left to stand to obtain a solution in which two layers are separated. After discarding the upper layer of the solution, acetone is again added and mixed, and water is added to the mixture and left. This results in a two-layer separation. The lower layer is collected, and acetone and water are distilled off under reduced pressure. Thereby, a desired silicone-modified epoxy resin is obtained.

In this synthesis method, substantially all of the organopolysiloxane used is added to the alkenyl group-containing epoxy resin. Therefore, in order to obtain a silicone-modified epoxy resin having a silicone modification degree of 10 to 60 parts by weight based on 100 parts by weight of the raw material epoxy resin as described above, the alkenyl group-containing epoxy resin is used. And the above-mentioned organopolysiloxanes can be achieved by adjusting the respective usage amounts to the above content ratios.

The silicone-modified epoxy resin used in the present invention has a silicone component content of 10 to 60 parts by weight based on 100 parts by weight of the starting epoxy resin.
It is in the range of parts by weight. When the silicone component is less than 10 parts by weight, the sealing material may be peeled off because of insufficient flexibility, and when the silicone component is more than 60 parts by weight, the gas barrier property is reduced and bubbles are easily mixed. That's why.

The curing agent used in the present invention usually functions as a curing agent for an epoxy resin, and one that produces a one-part resin composition is selected and used. That is, called a latent curing agent, in a mixture of an epoxy resin and a curing agent, can be stored at room temperature for a long time without changing its properties, when heated to a predetermined temperature, or given energy such as light In such a case, one having a function of rapidly curing is used. Specific examples of such latent curing agents include:
The following three types can be mentioned from the viewpoint of the chemical structure or the crosslinked structure of the cured epoxy resin.

1) High-melting-point active hydrogen compound A high-melting-point active hydrogen compound which is cured by performing an addition reaction with an epoxy group. Specific examples include dicyandiamide and organic acid dihydrazides such as adipic acid dihydrazide.

2) Salts of tertiary amines and imidazoles There are a high melting point dispersion type and a soluble type, and tertiary amines and imidazoles which dissolve, decompose and activate by heating to cause self-polymerization of epoxy resin by an anionic mechanism. Salt. Specific examples include amine imide, 2-methyl imidazole,
Examples thereof include 2-ethyl-4-methylimidazole and 2-phenylimidazole. These also function as curing accelerators.

3) Salts of Lewis acids and Bronsted acids Salts of Lewis acids and Bronsted acids which are activated by heating to cause the polymerization of epoxy resins by a cationic mechanism. Specific examples include boron trifluoride monoethylamine salt, Bronsted acid aliphatic sulfonium salt, aromatic diazonium salt, aromatic sulfonium salt, and the like.

[0052] Any of these latent curing agents is applicable to the present invention.

The silicone-modified epoxy resin composition used for forming the encapsulant of the present invention comprises the above-mentioned silicone-modified epoxy resin and a latent curing agent as essential components. An inorganic filler, a curing accelerator, a silane coupling agent and the like can be appropriately contained. Further, the composition may contain an epoxy resin not modified with silicone as long as the object of the present invention is not impaired.

The sealing material of the present invention is mainly used for a joint portion of an ink supply path of an ink jet head.
Even when used in a joint portion of an ink supply path from an ink tank to an ink jet head, a very excellent effect is exhibited. Further, it may be used for the wiring portion of the ink jet head.

The present invention provides an excellent effect particularly in an ink jet head and an ink jet apparatus of an ink jet printing system in which flying droplets are formed by utilizing thermal energy and recording is performed among the ink jet printing systems.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,723,129.
No. 740,796, and the invention is preferably carried out using these basic principles. This printing method is applicable to both so-called on-demand type and continuous type.

The printing method will be described briefly. An electrothermal transducer disposed corresponding to a sheet or a liquid path holding a liquid (ink), or a liquid (ink) corresponding to print information. By applying at least one drive signal to exceed the nucleate boiling phenomenon and to give a rapid temperature rise to cause the film boiling phenomenon, heat energy is generated, and film boiling is caused on the heat working surface of the ink jet head. . As described above, since bubbles corresponding to the driving signal applied to the electrothermal converter from the liquid (ink) can be formed one-to-one, it is particularly effective for an on-demand type printing method. By discharging the liquid (ink) through the discharge port by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. U.S. Pat. No. 4,463,463 discloses a driving signal in the form of a pulse.
No. 359 and 4,345,262 are suitable. In addition, U.S. Pat.
If the conditions described in the specification of JP-A No. 124 are adopted, more excellent recording can be performed.

The structure of the ink jet head includes a discharge port, a liquid flow path, and a liquid passage as disclosed in the above-mentioned respective specifications.
In addition to the configuration (linear liquid flow path or right-angle liquid flow path) in which an electrothermal converter is combined, it is disclosed in US Pat. No. 4,558,333 and US Pat. No. 4,459,600. As described above, the present invention also includes a configuration in which the heat acting portion is arranged in a bent region.

In addition, Japanese Unexamined Patent Publication (Kokai) No. 123670/1984 discloses a configuration in which a common slit is used as a discharge port of an electrothermal converter for a plurality of electrothermal converters, or absorbs a pressure wave of thermal energy. The present invention is also effective in a configuration based on JP-A-59-138461 which discloses a configuration in which an opening corresponding to a discharge unit is disclosed.

Further, as an ink jet head in which the present invention is effectively used, there is a full line type ink jet head having a length corresponding to the maximum width of a print medium that can be recorded by the ink jet apparatus. The full line head may be a full line configuration by combining a plurality of ink jet heads as disclosed in the above specification, or may be a single full line head formed integrally.

In addition, the ink jet head is replaceable with a chip type ink jet head which can be electrically connected to the apparatus main body or supplied with ink from the apparatus main body by being attached to the apparatus main body, or integrated with the ink jet head itself. The present invention is also effective when a cartridge type ink jet head provided in a fixed manner is used.

Further, it is preferable to add preliminary auxiliary means and the like to the ink jet device of the present invention since the ink jet device of the present invention can be further stabilized. More specifically, a preheating means using an electrothermal transducer or another heating element or a combination thereof, and a means for performing a preliminary ejection mode for performing ejection different from printing may be added. Is also effective for performing stable printing.

Further, the print mode of the ink jet apparatus is not limited to a mode in which only the mainstream color such as black is printed, but may be a mode in which the ink jet head is integrally formed or a plurality of ink jet heads. However, the present invention is also very effective for an apparatus provided with at least one of multiple colors of different colors or full color by mixing colors.

In the embodiment of the present invention described above,
Although the description has been made using the liquid ink, in the present invention, either an ink that is solid at room temperature or an ink that becomes soft at room temperature can be used. In general, in the above-described ink jet device, the temperature of the ink itself is adjusted within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. It is sufficient if the ink is in a liquid state.

In addition, an excessive temperature rise of the head or the ink due to thermal energy is positively prevented by using the energy of the state change from the solid state to the liquid state of the ink, or the purpose is to prevent the evaporation of the ink. Alternatively, an ink that solidifies in a standing state may be used. In any case, the ink is liquefied only by the application of thermal energy, such as the one in which the ink liquefies and is ejected as an ink liquid by the application of the thermal energy recording signal, and the one that starts to solidify when it reaches the print medium. The use of an ink having the following properties is also applicable to the present invention.

Such an ink is disclosed in JP-A-54-568.
No. 47 or Japanese Patent Application Laid-Open No. 60-71260, while being held as a liquid or solid substance in a concave portion or a through hole of a porous sheet, facing the electrothermal converter. It is good also as a form.

In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0068]

EXAMPLES describes experiments conducted by the present inventors in experiments below.

The present inventors have found that the sealing material provided in the ink-jet head has a problem in the prior art, namely, that bubbles are mixed into the ink flow path and the common ink chamber over a long period of use, In view of the problem of peeling of the sealing material when using an alkaline ink, the possibility of creating a sealing material having sufficient airtightness and excellent ink resistance was examined through experiments. In other words, paying attention to the excellent gas barrier properties of epoxy resin, while exhibiting this gas barrier property, it solves the problem of the stress of epoxy resins, and furthermore, the sealing material with better ink resistance than before The present inventors have examined the following experiments A-1 to A-11 to determine whether or not the silicone-modified epoxy resin composition found by the present inventors can contribute to solving the above-mentioned problems in the conventional inkjet head. In the following experiments A-1 to A-11, for realizing a desired sealing material, the ink resistance, the gas barrier property, and the low stress property of the sealing material were examined.

Experiment A-1 A silicone-modified epoxy resin was obtained by the above-mentioned synthesis method (2). That is, an organopolysiloxane having a hydrosilyl group represented by the following formula was added to a bisphenol A type epoxy resin Epicoat 828 (trade name, manufactured by Yuka Shell Co., Ltd.) in the presence of a platinum chloride catalyst. Addition by a hydrosilylation reaction gave a silicone-modified epoxy resin. The content of the silicone component in the obtained silicone-modified epoxy resin was 30 parts by weight based on 100 parts by weight of the raw material epoxy resin.

[0071]

Embedded image Novacure HX-3155, an amine-based latent curing agent
60 parts by weight (trade name, manufactured by Asahi Kasei Kogyo KK) were mixed with 100 parts by weight of the obtained silicone-modified epoxy resin. Further, an epoxy silane coupling agent A-187
5 parts by weight (trade name, manufactured by Nippon Unicar Co., Ltd.) were mixed to obtain a one-part silicone-modified epoxy resin composition.

Experiment A-2 Bisphenol F was used as a raw material for the silicone-modified epoxy resin.
Type epoxy resin Epicoat 807 (trade name, manufactured by Yuka Shell Co., Ltd.) and a silicone-modified epoxy in the same manner as in Experiment A-1, except that an organopolysiloxane having a hydrosilyl group represented by the above formula (I) was used. A resin was obtained. The content of the silicone component in the obtained silicone-modified epoxy resin was 40 parts by weight based on 100 parts by weight of the raw material epoxy resin.

Adeka Optomer SP-170 (trade name, manufactured by Asahi Denka Kogyo KK) as a cationic ultraviolet curing initiator was mixed with 2 parts by weight based on 100 parts by weight of the obtained silicone-modified epoxy resin. Further, an epoxy-based silane coupling agent A-187 (trade name, manufactured by Nippon Unicar) was added to 5
The parts by weight were mixed to obtain a one-part silicone-modified epoxy resin composition.

Experiment A-3 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was changed to 5 parts by weight based on 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-4 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was 10 parts by weight based on 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-5 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was 20 parts by weight with respect to 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-6 One liquid was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was 40 parts by weight with respect to 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-7 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was changed to 50 parts by weight based on 100 parts by weight of the starting epoxy resin. -Type silicone-modified epoxy resin composition.

Experiment A-8 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was 60 parts by weight based on 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-9 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was 70 parts by weight based on 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-10 One component was prepared in the same manner as in Experiment A-1, except that the content of the silicone component in the silicone-modified epoxy resin was 80 parts by weight based on 100 parts by weight of the starting epoxy resin. A silicone-modified epoxy resin composition was obtained.

Experiment A-11 Solid bisphenol A type epoxy resin epicoat 1001 was added to the raw material epoxy resin of the silicone-modified epoxy resin.
Experiment A- except that (trade name, manufactured by Yuka Shell) was used.
In the same manner as in Example 1, a silicone-modified epoxy resin was obtained. The content of the silicone component in the obtained silicone-modified epoxy resin was 20 parts by weight based on 100 parts by weight of the raw material epoxy resin.

Silicone-modified epoxy resin 1 obtained by using a phenolic resin curing agent in a methyl isobutyl ketone solvent
60 parts by weight were mixed with respect to 00 parts by weight.

Further, an epoxy silane coupling agent
A-187 (trade name, manufactured by Nippon Unicar) was mixed in an amount of 5 parts by weight to obtain a solvent-based one-pack silicone-modified epoxy resin composition.

Each of the silicone-modified epoxy resin compositions obtained in each of the above Experiments A-1 to A-11 was checked whether or not it is worthy of use as a sealing material in an ink jet head. The ink resistance, gas barrier properties, and stress required for the stop material were evaluated and examined by the methods described below. Ink resistance: The swelling of each silicone-modified epoxy resin composition (hereinafter referred to as a resin sample) with respect to the ink and the eluate in the ink were examined. That is, 5 g of each resin sample was applied to a highly alkaline ink (pH 10.7, composition: GLY 1
0.0, UREA 5.0, IPA 5.0, lithium hydroxide 0.4, ammonium sulfate 0.5) and Canon BJ Cartridge BC-0
Immersed in each of the 1 inks and used PCT for 12
After leaving at 0 ° C. for 10 hours, the degree of swelling and the presence or absence of eluted substances in the ink were evaluated by the following methods.

1) Evaluation of degree of swelling The weight of the resin sample was measured before and after immersion in the ink. % Was evaluated based on the criteria of x. Table 1 shows the evaluation results.

2) Evaluation of the presence or absence of eluted substances in the ink The ink in which the resin sample was immersed was examined for the presence of the organic impurities eluted in the ink by using a spectrophotometer. In addition, ICP-ACS (inductively coupled plasma ato
The presence or absence of inorganic impurities eluted in the ink was examined by mic emission spectroscopy). The obtained results are shown in Table 1 based on the following evaluation criteria.

：: When neither organic impurity nor inorganic impurity was observed; ×: When either organic impurity or inorganic impurity was observed.

The swelling here means deterioration of the material, and when the degree of swelling is large, a serious problem is caused in adhesion. Those having a weight change of 5% or less satisfy the requirements for the sealing material. In particular, those having a weight change of 1% or less have no problem such as separation at all, and are very excellent as sealing materials. By the way, elution of impurities into the ink leads to a problem that the impurities change physical properties of the ink and the ink cannot be ejected normally. Such eluting inorganic impurities include Cr, Si, Ca, Zn, Mg, Mn, Al, Fe, Ni, Cd, C
Metals such as u and Sn. The presence of such inorganic elutes may cause burns on the heater, or may react with gas in the air to form unwanted matter in the ink, causing nozzle clogging. The eluted organic impurities are solvents, plasticizers, unreacted substances, and the like. If there are such eluting organic impurities,
This may cause a change in the surface tension or viscosity of the ink, which may cause a failure in stable ejection. Further, if the eluting substance is colored, the color of the ink may be changed.

Gas barrier property (airtightness): The gas barrier property (airtightness) of each resin sample when used as a sealing material was evaluated by examining gas permeability. That is, the gas barrier property was measured by a fully automatic gas permeability tester L100-4002 (trade name, manufactured by Dr. LYSSY). Air was used as gas. The measurement results were evaluated according to the following criteria, and the evaluation results are shown in Table 1.

◎: Gas permeability of 500 ml / m ² · d · atm or less; ○: Gas permeability of 500 ml / m ² · d · atm to 1000 ml / m
If: ² · d · atm; ×: when the gas permeability is higher than ^{1000ml / m 2 · d · atm} .

Note that ml / m ² · d · atm is 1 at atmospheric pressure.
What ml of gas per 1 m ² are representative of whether it has transmitted the day. Those having a gas permeability of 1000 ml / m ² · d · atm or less need not be subjected to special treatment by intrusion of air bubbles in ordinary use. The gas permeability is 500ml / m ²
In the case of d · atm or less, air bubbles do not invade even when the unused state lasts for three months without special treatment.

Stress: A heat cycle test was carried out for the purpose of examining the stress when each resin sample was used as a sealing material. In the heat cycle test, a three-zone heat cycle test and a two-zone heat cycle test described below were performed, and in each test, the peeling state of each resin sample as a sealing material was evaluated.

Three-zone heat cycle test: Resin sample
After coating 5 g on a glass substrate and curing, the substrate is coated with a highly alkaline ink (pH 10.7, composition: GLY 10.0, URE
A 5.0, IPA 5.0, Lithium hydroxide 0.4, Ammonium sulfate 0.5), immersed in each zone of (1) -30 ° C, (2) room temperature, (3) 60 ° C for 2 hours in each environment From -30 ° C to 60 ° C via room temperature.
The heat cycle of these three zones at -30 ° C. and at room temperature was set as one cycle, and the sample on the glass substrate after 10 cycles was examined using a microscope for the presence or absence of peeling.

Two-zone heat cycle test: A test material was prepared in the same manner as in the three-zone heat cycle test, and each sample was placed in an environment of (1) -30 ° C. and (2) 60 ° C. in each zone.
The two-zone heat cycle is set to -30 ° C to 60 ° C and returned to -30 ° C for 1 hour.
As a cycle, the sample on the glass substrate after 50 cycles was examined using a microscope for the presence or absence of peeling.

The obtained results were evaluated according to the following evaluation criteria.
Table 1 shows the obtained evaluation results.

◎: When peeling was not observed in any of the three-zone heat cycle test and the two-zone heat cycle test; 場合: When peeling was observed only in the two-zone heat cycle test; When peeling is observed in both of the two-zone heat cycle tests.

[0098] It should be noted that those which do not peel off in the three-zone heat cycle test can be said to have no peeling even in a normal use environment. In addition, it can be said that a film which does not peel off in the two-zone heat cycle test does not peel even in a severe use environment which can be considered normally.

Overall evaluation: The above evaluation items were comprehensively evaluated for evaluation. The evaluation was performed according to the following evaluation criteria, and the results are shown in Table 1.

A: When all the evaluation items are satisfactory; A: When some of the evaluation items are not sufficiently satisfied but there is no practical problem; X: When there is a performance problem.

[0101]

[Table 1]

As a comparative example, the following 4 was used as a conventional sealing material.
Two samples were prepared and evaluated in the same manner as described above, and the results are shown in Table 2.

Experiment B-1 One component, a dealcohol-type moisture-curable silicone sealant TSE397 (trade name, manufactured by Toshiba Silicone Co., Ltd.) was used as a sealing material. The curing was performed at 50 ° C. for 8 hours.

Experiment B-2 One-component epoxy resin Vinal E-405 (trade name, manufactured by Kanae Industries Co., Ltd.) was used as a sealing material. The curing is 1
The test was performed at 20 ° C. for 60 minutes.

Experiment B-3 One component, anaerobic, ultraviolet curable, modified acrylate resin
4X678B (trade name, manufactured by Chemitech) was used as a sealing material. In addition, curing is performed after irradiation of ultraviolet rays 450 mj / cm ² ,
Performed by heating at 0 ° C. for 5 minutes.

Experiment B-4 Two components, an elastic epoxy resin ECOBOND 45LV / 15LV (trade name, manufactured by Grace Japan) were mixed at a ratio of 100/150 and used as a sealing material. In addition, curing is 70 ° C.
For 120 minutes and 90 ° C. for 40 minutes.

[0107]

[Table 2] From the results shown in Tables 1 and 2, the following was found.

That is, with respect to the ink resistance, the samples of Experiments A-3 and B-2, 3 and 4 exhibited swelling of 5% or more in both the alkali ink and the BC-01 ink. It is presumed that the resin sample of Experiment A-3 had a small content of the silicone component, so that the properties were close to those of the epoxy resin and could not exhibit sufficient performance against swelling.

On the other hand, regarding the elution of impurities into the ink, the resin samples of Experiments A-11 and B-3 and 4 showed that impurities eluted from both the alkaline ink and the BC-01 ink. Was observed. Here experiment A-
Regarding the sample No. 11, it is considered that the solvent in the silicone-modified resin was particularly eluted into the ink.

Regarding the gas barrier properties, the resin samples of Experiments A-9 and 10 and Experiments B-2 and 3 contained 1000 ml of resin.
The value was higher than / m ² · d · atm. Here, regarding the samples of Experiments A-9 and A-10, since the content of the silicone component was relatively large, it was presumed that the properties were higher than those of silicone and the gas barrier properties could not be sufficiently exhibited.

Regarding the stress, Experiment A-3 and Experiment B-
Peeling was observed in the resin samples 2 and 3 also in the three-zone heat cycle test. Here, it is presumed that the sample of Experiment A-3 had a small content of the silicone component, and thus could not exhibit sufficient performance against stress because the property was close to that of the epoxy resin and the flexibility was low.

From the above results, according to the encapsulant made of the silicone-modified epoxy resin of the present invention described above, the joint portion of the members constituting the ink supply path of the ink jet head is made to have a hermetically sealed portion, and to be peeled off. It will be understood that the problem can be avoided. Among the above-mentioned experiments, those belonging to the present invention were obtained in Experiments A-1, 2, 4 to 7, and those that are more preferable in terms of overall performance as a sealing material for an ink jet head are the experimental ones. A-
1, 2 and 6.

Next, the experiment A described above as an example of the present invention.
The performance of the silicone-modified epoxy resin composition obtained in -1 was verified using the same as a sealing material for an inkjet head. As comparative examples, Experiments A-11 and B-1
The performance of the sealing material obtained in the above was verified using an ink jet head.

Embodiment 1 FIG. 5 is a sectional view of a main part of an ink jet head according to this embodiment. You. In the figure, 2 is an ink supply unit,
4 is an aluminum base plate, 101 is a silicon substrate, 1
04 is an ink passage wall, 105 is a top plate, 106 is an ink filter, 109 is a discharge port, and 110 'is a sealing material.

The one-pack type silicone-modified epoxy resin composition obtained in Experiment A-1 was applied to a top plate 105 of an ink jet head shown in FIG. 5 prepared by a conventional method to a thickness of 50 μm by screen printing. Unit 2
Were bonded and cured at 80 ° C. for 4 hours to prepare an ink jet head.

The liquid chamber of the ink jet head thus prepared was charged with a highly alkaline ink (pH 10.7, composition: GL).
Y 10.0, UREA 5.0, IPA 5.0, lithium hydroxide 0.4, ammonium sulfate 0.5), and after standing for 10 days in an environment of 35 ° C. and 10% humidity, 20 g of the above When printing was performed on the ink tank having the removed ink until the ink in the tank was used up, no printing failure or non-discharge occurred, and good printing could be performed to the end without performing the bubble removing process.

Comparative Example 1 An ink jet head was prepared in the same manner as in Example 1, except that the one-pack type silicone-modified epoxy resin composition obtained in A-11 was used as a sealing material for the ink jet head.

The ink-jet head thus prepared was placed in a liquid chamber of the ink-jet head in a high alkali ink (pH 10.7, composition: GLY 1) in the same manner as in Example 1.
0.0, UREA 5.0, IPA 5.0, lithium hydroxide 0.4, ammonium sulfate 0.5), and left for 10 days in an environment of a temperature of 35 ° C. and a humidity of 10%. When printing was performed on the ink tank having the ink until the ink in the tank was used up, non-discharging and the like did not occur, but a part of the printing was blurred.

Comparative Example 2 An ink jet head was prepared in the same manner as in Example 1 except that a dealcohol-type moisture-curable silicone sealant B-1 was used as a sealing material for the ink jet head.

In the same manner as in Example 1, the ink jet head thus prepared was placed in a liquid chamber of the ink jet head in a high alkali ink (pH 10.7, composition: GLY 10.
0, UREA 5.0, IPA 5.0, lithium hydroxide 0.4, ammonium sulfate 0.5), and left for 10 days in an environment at a temperature of 35 ° C. and a humidity of 10%.
When printing was performed on the ink tank having the above-described ink of 20 g until the ink in the tank was used up, non-discharge was partially observed, and blurring of the print was also observed.

[0121]

As described above, when the silicone-modified epoxy resin composition of the present invention is used to seal the joining portion of the members constituting the ink supply path of the ink jet head as described above, the sealing portion is sealed. It can be understood that a desired ink-jet head which has high airtightness and can be free from problems such as peeling and which can always perform stable ink ejection to provide high quality printing can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an example of a conventional inkjet head.

FIG. 2 is a cross-sectional view of a main part of the ink-jet head when a cross-section taken along line AB of the ink-jet head of FIG.

FIG. 3 is a schematic perspective view of a discharge element portion of the inkjet head shown in FIG.

FIG. 4 is a schematic explanatory view showing an example of an ink jet device equipped with the ink jet head shown in FIG.

FIG. 5 is a sectional view of a main part of the ink jet head according to the present invention.

[Explanation of symbols]

 2 Ink supply unit 4 Aluminum base plate 101 Silicon substrate 104 Ink passage wall 105 Top plate 106 Ink filter 109 Discharge port 110 'Sealing material

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Shigeo Toba 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-4-202217 (JP, A) JP-A-3 -719 (JP, A) JP-A-4-351630 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/16-2/175 B41J 2/04-2/05 C08G 59/00-59/72

Claims (22)

(57) [Claims] 1. A solvent-free, one-part type silicone-modified epoxy resin which is liquid at room temperature and substantially formed of a composition comprising the silicone-modified epoxy resin and a latent curing agent. Ink jet with sealed encapsulant
A head, wherein the silicone-modified epoxy resin is
Silicone component based on 100 parts by weight of raw epoxy resin
10 to 60 parts by weight of the ink jet
Head. 2. The ink jet head according to claim 1, wherein said silicone-modified epoxy resin is prepared using epoxy resin and organosiloxane as raw materials. 3. The epoxy resin is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AD type epoxy resin, a bisphenol AF type epoxy resin, a novolak type epoxy resin and a modified resin thereof which are liquid at room temperature. The ink jet head according to claim 2 , wherein: Wherein said organosiloxane, claims and having an epoxy group, an alkoxy group, a hydroxyl group, an amino group, at least one hydrosilyl group
Item 3. An inkjet head according to Item 2 . 5. The ink jet head according to claim 1, wherein the latent curing agent is a high-melting-point active hydrogen compounds. 6. The ink jet head according to claim 1, wherein the latent curing agent is tertiary amine or a salt of imidazole. 7. The ink jet head according to claim 1, wherein the latent curing agent is a salt of a Lewis acid or Bronsted acid. 8. The ink jet head according to claim 1, wherein the composition further contains a silane coupling agent. 9. The ink jet printer according to claim 1, wherein said sealing material is provided at a joint portion of constituent members forming an ink supply path.
2. The inkjet head according to item 1. 10. The ink-jet head according to claim 1, wherein an electric energy is applied by an electrothermal converter to generate heat to cause a change in the state of the ink to discharge the ink. 11. The ink jet head according to claim 1, wherein the ink jet head is a full line type having a plurality of discharge ports provided over the entire width of a print area of a print medium. 12. An ink-jet apparatus having at least an ink-jet head for discharging ink and a recovery device for recovering the ink-jet head, wherein the ink-jet head is a non-solvent, one liquid which is liquid at normal temperature. Having a sealing material substantially consisting of a silicone-modified epoxy resin of a mold, formed using a composition comprising the silicone-modified epoxy resin and a latent curing agent ;
First, the silicone-modified epoxy resin is a raw material epoxy resin
10 to 60 parts by weight of silicone component based on 100 parts by weight of fat
Ink jet apparatus which is a part. 13. The silicone-modified epoxy resin,
13. The ink-jet apparatus according to claim 12 , wherein the ink-jet apparatus is made using epoxy resin and organosiloxane as raw materials. 14. The epoxy resin is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol AD type epoxy resin, a bisphenol AF type epoxy resin, a novolak type epoxy resin or a modified resin thereof which is liquid at room temperature. The inkjet device according to claim 13 , wherein: 15. The organosiloxanes claims, characterized in that it comprises an epoxy group, an alkoxy group, a hydroxyl group, an amino group, at least one hydrosilyl group
Item 14. An ink jet device according to item 13 . 16. The ink jet apparatus according to claim 12 , wherein said latent curing agent is a high melting point active hydrogen compound. 17. The ink-jet apparatus according to claim 12 , wherein said latent curing agent is a salt of a tertiary amine or imidazole. 18. The method of claim, wherein the latent curing agent is a salt of a Lewis acid or Bronsted acid 12
An inkjet device according to item 1. 19. The ink-jet apparatus according to claim 12 , wherein said composition further contains a silane coupling agent. 20. A claims, characterized in that provided at the junction of the components of the sealing material constituting an ink supply path
13. The inkjet device according to 12 . 21. The ink-jet apparatus according to claim 12 , wherein electric energy is applied by an electrothermal converter to generate heat to cause a change in the state of the ink to discharge the ink. 22. An ink jet apparatus according to claim 12 , wherein said ink jet apparatus is a full line type having a plurality of discharge ports provided over the entire width of a print area of a print medium.